She later added: “I’m just really grateful that anyone is still listening.

Katy Perry said Glastonbury made her feel cool (Yui Mok/PA)

“As the great Rihanna says, nothing is promised. I started almost 10 years ago.”

Perry arrived on stage dressed in a sequinned bodysuit with an eye design on the chest and was flanked by a troupe of dancers in lycra bodysuits and a series of headwear including television screens, fluffy pink blocks and mouths with eyeballs inside.

The singer thanked fans for their support (Yui Mok/PA)

She opened with some new tracks, but then launched into some of her greatest hits including Teenage Dream, Firework, Dark Horse and E.T.

Later this evening, headline act Foo Fighters will close the day’s music.

Friday night’s headline act was Radiohead and tomorrow will see Ed Sheeran take the top billing.